This section introduces aspects that may help facilitate a better understanding of the disclosure. Accordingly, these statements are to be read in this light and are not to be understood as admissions about what is or is not prior art.
The industrial competitiveness of the 2G (cellulose) ethanol depends on achieving efficient production and use of cellulase enzymes. Cellulase production by filamentous fungi may be achieved through either solid-state fermentation (SSF) or submerged fermentation (SmF). Despite many advantages of SSF over SmF, enzyme production in large-scale SSF bioreactors is hindered by low solids loadings, or if high solids are used, by solids handling and mass and heat transfer gradients during the cultivation process (Barrios-Gonzalez, 2012; Cunha et al., 2012; Esperança et al., 2014). Submerged cultivations with high solids loadings remain challenging since mass transfer and gas hold-up limitations are also compounded by viscosity increases that occur during the first hours of cultivation as a result of fungal growth. There is therefore an unmet need for enhancing production of cellulase components.